Wireless access points (APs) have been used with wireless local area networks (WLANs) to exchange communication signals with wireless mobile and fixed clients. Such wireless APs are typically comprised of single or dual frequency band radios having separate or shared omnidirectional or low gain (typically, less than 10 dBi) directional antennas. The location, frequency band assignment, and antenna characteristics of such APs are of interest to the network management function insofar that they affect network coverage. However, the AP orientation is of little interest other than to know how to use a low gain directional antenna (such as when an AP is located on a wall or on a high ceiling).
However, it is expected that the next generation of APs will use multiple antennas for sector coverage and/or array antennas for beam forming coverage using multiple simultaneous frequency bands. The network management function for such multichannel APs or adaptive array APs therefore becomes considerably more complex. At issue is the fact that in addition to location, the orientation of the AP must be known in order to ascertain in which direction particular antenna beams will provide coverage.
Additionally, AP orientation knowledge is required if “location based services” are to be incorporated into a wireless network system. Location based services enable the detection of the position in space of a client device or other type of device seeking access to the network. Types of location based services may include client identification and location, rogue client identification and location, equipment location, perimeter security, and a host of other functions. These functions require knowledge of the physical position of the AP, as well as orientation of the AP with respect to three-dimensional space.
In a typical AP installation, the orientation of the AP could be noted by the installer at the time of deployment, who would then forward that information to the network administrator. However, such a manual process is prone to error since the function might contain observational or notational error. This could lead to erroneous results in the implementation of the location based services.